<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.6.10/dist/vue.js"></script>
</head>

<body>
    <div id="app">
        <button @click="increment">累加</button>
        <button @click="incrementN(3)">累加n</button>
        <h1>count:{{count}}</h1>
    </div>
    <script>
        Vue.config.productionTip = false;
        
        const vm = new Vue({
            el: "#app",
            data() {
                return {
                   count:0 
                }
            },
            methods:{
                increment(){
                    // 在插值语法中可以直接访问vm身上的属性和方法但是在事件回调函数中，必须先通过this访问到vm才能
                    this.count++;
                },
                incrementN(n){
                    this.count += n;
                }
            }
        })
</script>
</body>

</html>